Gas feeding system for chemical vapor deposition reactor and method of controlling the same

Abstract

A gas feeding system for applications such as chemical vapor deposition (CVD) is provided. The gas feeding system comprises a plurality of reactant source supply apparatuses that are connected to a reactor to supply different reactant sources therein discontinuously or sequentially. The gas feeding system includes a pass valve that is disposed in a supply tube between inlet and outlet valves of the reservoir for containing the reactant source. With the pass valve, the carrier gas passing therethrough flows into the reactor or the evacuation valve without passing through the reservoir when the inlet valve and outlet valve are closed to prevent the waste of non-use reactant sources. With the present invention gas feeding system, the uniformity and quality of the deposited film can be improved and the waste of reactant source can be reduced.

Description

The present invention relates to a gas feeding system, and more particularly, to a gas feeding system for chemical vapor deposition (CVD) reactor capable of improving the uniformity and quality of deposited film in the manufacture of semiconductor devices. The present invention also relates to a method of controlling the same which prevents the waste of reactant source.It is often desirable to form films of uniform thickness on a substrate in semiconductor manufacturing. Accordingly, considerable efforts have been made to improve both equipment and manufacturing process.Recently, many processes for forming a high quality film were developed using surface reaction on a semiconductor substrate: processes such as using discontinuous supplies of a reactant source on a substrate, atomic layer epitaxy, and sequential supplies of a reactant sources on a substrate. The films formed by the above processes have enhanced uniformity and quality, and minimized impurity concentration therein, How...

AI Technical Summary

Benefits of technology

It is another object of the present invention to provide a gas feeding system for chemical vapor deposition reactor and method of controlling the same capable of preventing the waste of non-use and idling gaseous reactant sources when not feeding the sources into the reactor.

In order to accomplish the aforementioned objects, the present invention provides a gas feeding system for chemical vapor deposition reactor having at least one reactant source supply apparatus, the supply apparatus each comprising: a mass flow controller for controlling the flow rate of a carrier gas which carries a reactant source; a reservoir for containing the reactant source, the reservoir having inlet and outlet valves for controlling the flow of the carrier gas through the reservoir; a supply valve for controlling the mass flow of the reactant source carried by the carrier gas to the reactor; an evacuation valve disposed between the outlet valve and the supply valve, the evacuation valve evacuating the carrier gas or the reactant source toward a vacuum pump; and a pass valve disposed between the inlet valve and the outlet valve so that the carrier gas passing therethrough flows into the reactor or the evacuation valve, the pass valve stabilizing the carrier gas mass flow controller as well as preventing the leakage of the reactant source from the reservoir.

Preferably, the reactant source supply apparatus further comprises a first purge gas supply unit disposed between the supply valve and the reactor so as to prevent the backward flow of other reactant sources into the source supply apparatus upon deposition reaction. More preferably, the first purge gas supply unit further comprises a mass flow controller for controlling the flow of purge gas therethrough to a constant level.

Problems solved by technology

The films formed by the above processes have enhanced uniformity and quality, and minimized impurity concentration therein, However, the above processes have a disadvantage of the waste of non-use and idling gaseous reactant sources.

However, such processes also have disadvantages that uniformity in film thickness, film quality, and impurity concentration are considerably affected depending upon the flow direction, flow velocity, temperature, types of used reactant sources.

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